The following descriptions and examples are not admitted to be prior art by virtue of their inclusion within this section.
In optical fiber communications systems, a transmitter may include a semiconductor laser (e.g., a laser diode) that generates the modulated digital or analog optical signal, which is optically coupled into one end (input or light-receiving end) of an optical fiber. At the other end of the fiber (output or light-transmitting end), a receiver may receive the optical signals. The receiver may include a photodetector optically coupled to the fiber to generate an electrical signal in response to the optical signal impinging thereon.
Various modules, assemblies or packages may be used to hold the laser and/or photodetector and other optical components (such as collimation and coupling lenses, isolators, and the like). The optical fiber is coupled to the package such that the fiber is aligned with and optically coupled to the laser and/or photodetector. The process of aligning an optical fiber with an optoelectronic package, such as a laser diode package, and fixing it in place is sometimes known as fiber pigtailing.
An optoelectronic package may include a housing portion (e.g., containing the laser and/or photodetector) and a fiber pigtail portion that connects the fiber to the housing portion. In some packages, such as a TO (transistor outline) can type package, the housing portion and the fiber pigtail portion are generally coaxial. For example, the fiber end may be disposed in a pigtail portion including a rigid cylindrical ferrule, which is itself mounted inside a cylindrical ferrule housing. The pigtail portion may also include an isolator. A TO can housing may include a substantially cylindrical portion having a lens disposed in an opening in the top portion thereof, which can be disposed between the laser and the fiber end. The fiber ferrule housing is mounted to the TO can housing. During the last stage of a coaxial packaging process, for example, the pigtail portion (i.e., the fiber ferrule) may be welded to the TO can.
Subsequently, during testing, it may be determined that some of the assembled optoelectronic devices may be defective (e.g., the lasers may be defective). If the pigtail portion cannot be separated from the housing portion containing the defective component, the entire assembly, including the pigtail isolators, usually is discarded. Some attempts have been made at separating the pigtail portion from the housing portion using conventional tools (e.g., using pliers); however, the use of such conventional techniques tends to ruin the isolator, for example, by breaking the magnetic ring in the isolator. Thus, the conventional techniques generally prevent the pigtail portions including the isolators from being reused after they are coupled to housings containing defective components.